• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1006-1013
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• 1998

The present study was conducted to investigate the effect of different levels of ethanol ingestion on 131ate metabolism and plasma homocysteine concentration in Sprague-Dawley male rats receiving 0, 10, 30% of their caloric intake as ethanol for S weeks. Diets containing 10% ethanol had no effect on plasma and red blood cell(rbc) 131a1e. However, in rats fed a 30% ethanol diet, rbc folate increased and plasma 131ate decreased significantly, In the rats maintained first on a 30% ethanol diet for S weeks and then on a control diet for 2 weeks, the levels of plasma and rbc f31ate were normalized by withdrawal of ethanol. Urinary fo1ate excretion increased markedly in rats fed 10% and 30% ethanol diets and decreased to 51% of controls by withdrawal of ethanol. Plasma homocysteine concentration increased significantly in rats fed a 30% ethanol diet. The results suggest that chronic ingestion of ethanol increased urinary 131ate excretion markedly, which may decrease plasma 131ate and deplete liver folate.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.43.1-43.1
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• 2009

Electromagnetic radiation at the plasma frequency and its second harmonic, the so-called plasma emission, is fundamental process responsible for solar type II and III radio bursts. There have also been occasional observations of higher-harmonic plasma emissions in the solar-terrestrial environment. We will present that the simulation effort on characterizing the electron beam-generated plasma emission process at POSTECH. We have developed fully electromagnetic particle-in-cell (PIC) simulation code with three dimensions. We simulated harmonic plasma emission with various beam condition. Qualitative comparison with the traditional plasma frequency and second harmonic radiation theory is in good agreement. Higher harmonic emissions agree with the theory of coalescence of Langmuir and harmonic EM wave.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.178.2-178.2
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• 2013

Conventional ultraviolets A,B,C are known to be very important factor of killing, changing surface properties of biological cells and materials. It is of great importance to investigate the influence of extreme ultraviolet (EUV) exposure on the biological cell. Here we have studied high density EUV plasma and its emission characteristics, which have been generated by plasma focus device with hypercycloidal pinch (HCP) electrode under various Ar gas pressures ranged from 30~500 mTorr in this experiment. We have also measured the plasma characteristics generated from the HCP plasma focus device such as electron temperature by the Boltzman plot, plasma density by the Stark broading method, discharge images by open-shuttered pin hole camera, and EUV emission signals by using the photodiode AXUV-100 Zr/C.

• Korean Journal of Veterinary Research
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• v.34 no.2
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• pp.287-299
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• 1994

Plasma protein which has been known as one of nonspecific immunostimulators was added to feedstuff to examine its effect on the enhancement of cellular immune response in porcine immune system. A total of 40 piglets, 20 male and 20 female each, were fed for 30 days with or without plasma protein. The peripheral blood were collected and analyzed for the investigation of leukocyte subpopulations and their activities by using a panel of monoclonal antibodies specific to porcine leukocyte differentiation antigens and flow cytometry. The results obtained as follows. 1. Subpopulations expressing major histocompatibility complex(MHC) class I antigen were $96.2{\pm}3.1%$ and $86.6{\pm}3.8%$ in piglets fed with plasma protein and in piglets fed without plasma protein, respectively. 2. Proportion of leukocyte subpopulation expressing MHC class II antigens were significantly higher in the piglets fed with plasma protein than ones without plasma protein. The proportion was $27.6{\pm}3.6%$ and $16.6{\pm}2.2%$ in MHC class II DQ antigen, and $28.1{\pm}2.0%$ and $20.0{\pm}0.3%$ in MHC class II DR antigen, respectively. 3. A significant increase in the proportion of cells expressing poCD2 was not found in piglets fed plasma protein. 4. Proportion of subpopulation expressed porcine(Po) CD4 antigens which specific to helper T lymphocytes were not increased (18.3-19.1% vs. 25.6-28.8%), rather slightly decreased, in plasma protein-treated group. 5. The most important increase of proportion in plasma protein-treated group was the leukocyte subpopulation specific to $poCD8^+$ T cytotoxic/suppressor lymphocytes. The expression level was significantly higher up to 45.9-47.1% in plasma protein-treated group in comparing with 29.7-33.0% in non-plasma protein-treated group. 6. Lymphoblastogenetic responses using different concentrations of Con A mitogen and plasma protein has found that the responses of lymphocyte from piglets fed plasma protein was significantly activated (p<0.01). The activities measured by 3[H]-thymidine incorporation showed 3-6 times stronger in plasma protein-treated group than those in non-plasma protein-treated group. The study has concluded that plasma protein, which has known as a nonspecific immunostimulator, may have an immunoenhancing activities in porcine lymphoid system by increase the activated cell proportions and their blastogenetic properties which is critical to host immune responses.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.24-24
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• 2018

One of the challenges in tissue engineering is the design of optimal biomedical scaffolds, which can be governed by topographical surface characteristics, such as size, shape, and direction. Of these properties, we focus on the effects of nano - to micro - sized hierarchical surface. To fabricate the hierarchical surface structure on poly(${\varepsilon}$-caprolactone) (PCL) film, we employed a nano/micro-casting technique (NCT) and modified plasma process. The micro size topography of PCL film was controlled by sizes of the micro structures on lotus leaf. Also, the nano-size topography and hydrophilicity of PCL film were controlled by modified plasma process. After the plasma treatment, the hydrophobic property of the PCL film was significantly changed into hydrophilic property, and the nano-sized structure was well developed, as increasing the plasma exposure time and applied power. The surface properties of the modified PCL film were investigated in terms of initial cell morphology, attachment, and proliferation using osteoblast-like-cells (MG63). In particular, initial cell attachment, proliferation and osteogenic differentiation in the hierarchical structure were enhanced dramatically compared to those of the smooth surface.

• Journal of Information Display
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• v.2 no.1
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• pp.24-33
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• 2001

The characteristics of the reset and the address discharges of an alternating current Plasma Display Panel (ac PDP) were studied using 2-dimensional numerical discharge cell simulation. We investigated the wall charge variations during the reset discharge adopting ramping reset pulse and the subsequent addressing discharge. The roles of the ramping reset scheme can be divided into two stages, each electrode gathers wall charges during ramping-up of the initial stage and the built-up wall charges are lost during ramping-down of the later stage. Address discharge does not only change the wall charge distributions on the address and the scan electrodes but also on the sustain electrode. The increase in the wall charges on the sustain electrode was observed with the variation of the applied voltage to the sustain electrode during the address period. The increase of the applied voltage to the sustain electrode during the address period is expected to induce the decrease of the sustain voltage during the display period.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.04b
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• pp.56-58
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• 1997

최근 polyolefin계열의 고분자 분리막이 많이 사용되고 있는데 특히 그 중 polypropylene막은 특성상 내약품성 및 내열성이 뛰어나 막 손상이나 성능 저하가 비교적 적은 고분자 막으로 평가되고 있다. 그러나 재질의 소수성 특성 때문에 심각한 fouling을 유발하게 되어 이를 방지하기 위해 막 표면을 hydrophilic agent로 개질 시켜 fouling을 제어하는 기술이 진행되고 있다. 일반적으로 막 재질을 개질 시키기 위하여 sulfonating agents, ozone, 그리고 hydrophilic monomer등을 grafting하는 방법들이 사용되고 있는데, 이는 공정상의 어려움이 있고 완벽한 친수성의 부여를 기대하기가 어렵다. 또한 막 기공 구조의 변화와 붕괴를 초래한다는 단점이 있다. 이밖에 hydrophilizing agent 등을 이용하여 wetting시킴으로써 일시적인 친수화 처리를 하는 방법이 있다. 그러나 이 방법은 membrane matrix로 부터 hydrophilizing agent가 새어 나가므로 영구적으로 사용할 수 없으며, 특히 의료용 분리막으로 이용될 경우 유출된 hydrophilizing agent가 cell membrane을 공격하여 cell 분해와 같은 인체에 해로운 결과를 초래하기 때문에 부적당하다. 최근 들어 저온 plasma를 이용한 표면 개질의 방법이 연구되고 있는데, 이는 plasma가 고분자 물질의 구조나 화학적 반응성과는 상관없이 모든 고분자 물질의 표면을 일정하게 개질 시킬 수 있으며 여타의 다른 방법들과는 달리 막 제조시 residual solvent의 문제점과 swelling의 문제점들이 발생하지 않는 장점 때문에 최근 각광받고 있는 기술 중의 하나이다. 또한 다른 방법에 비해 막과 plasma와의 강한 흡착력 때문에 영구적 친수성을 가지게 할 수 있다. 본 연구에서는 저온 plasma를 이용한 표면 개질이 막의 친수성 향상 및 fouling 방지에 미치는 영향에 대하여 조사하였다.

• Food Science and Preservation
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• v.7 no.1
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• pp.124-131
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• 2000

Antibacterial activities of powdered spices(garlic , ginger, cinnamon and clove) against pathogenic Escherichia coli )157:H7 and Staphyloccus auresus were investigated. Spice powder was added in was exponetial phase of each bacterial culture . Growth inhibition was determined by the absorbance at 660nm and morphological changes of the cells were observed by transmission electron microscope (TEM). Ginger powder has the highest antibacterial activity, following cinnamon , clove and garlic has the least activity.Growth of Escherichia coli O157:H7 and Staphyloccus aureus were completely inhibited within 5 hours after addition of 1 % of garlic , 0.3% of ginger or cinnamon , 0.5% of clove powder on the exponential phase of the cells. Spice untreated cells of E. coli and S. aureus, the cytoplasm was entirely surrounded by rigid cell wall and cell walls formed a smooth layer well attached to the plasma membrane. In the cells of E. coli and S. aureus treated with spice powder, cell wall and plasma membrane were lysed and severely damaged. E.coli cells growth in the presence of spice powder showed plammolysis, the loss of electron dense material, the formation of extra cellular blebs and cytoplasm burst out from the cell. S .sureus cells grown in the presence of spice powder showed swell of cell wall, the loss of electron dense material , coagulation of cell cytoplasm and formation of extra cellular blebs. Severely damaged cells of S. aureus lost whole cytoplasm and left as ghost of the cell. Spice powder stimulated autolyssi and induced cell death.

• Korean Journal of Materials Research
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• v.29 no.5
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• pp.317-321
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• 2019

We investigated the characteristics of nano crystalline silicon(nc-Si) thin-film solar cells on graphite substrates. Amorphous silicon(a-Si) thin-film solar cells on graphite plates show low conversion efficiency due to high surface roughness, and many recombination by dangling bonds. In previous studies, we deposited barrier films by plasma enhanced chemical vapor deposition(PECVD) on graphite plate to reduce surface roughness and achieved ~7.8 % cell efficiency. In this study, we fabricated nc-Si thin film solar cell on graphite in order to increase the efficiency of solar cells. We achieved 8.45 % efficiency on graphite plate and applied this to nc-Si on graphite sheet for flexible solar cell applications. The characterization of the cell is performed with external quantum efficiency(EQE) and current density-voltage measurements(J-V). As a result, we obtain ~8.42 % cell efficiency in a flexible solar cell fabricated on a graphite sheet, which performance is similar to that of cells fabricated on graphite plates.

• The Journal of Dong Guk Oriental Medicine
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• v.7 no.2
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• pp.155-162
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• 1999

Euonymus alatus(Thunb.) Sieb has been used for cancer theraphy such as Liver cancer, esophagus cancer, stomach cancer, and uterine cancer in folk. Eupolyphaga simemsis(ES) extracted from Euonymus alatus(Thunb.) Sieb increases HDL-C/TC ratio and LCAT activity. TGF-${\beta}$ and Insulin has been Knoen as factors to induce the supression of proliferation of Hep3B, Human hepatoblastoma cell. Plasma HDL3-C involved in carbohydrate methabolism in the liver was maintained in low level by Euonymus alatus(Thunb.) Sieb. The low level of plasma HDL3-C suppresses the transition from normal liver to Fat liver. Finally, this resuly in suppression of cancer in liver. In this study, Euonymus alatus(Thunb.) Sieb showed higher cell toxicity in hepatoblastoma cell(Hep3B) compared to the uterine cancer cell(HeLa). This means Euonymus alatus(Thunb.) Sieb seems not to affect in the all kinds of cancer. In future, we will study whether Euonymus alatus(Thunb.) Sleb have an effect on the liver cancer induced by virus and hepatocellular carcinoma. Also, the mechanims of suppression of cell proliferation in HCC need to investigated.